Re: Problem with subArray - unnecessary memory allocation

[Thomas Birke <Thomas.Birke@bessy.de>]

Noboru Yamamoto wrote:
> Hi,
>
> We encountered same problem when we building KEKB control system.
> Our solution is to modify EPICS base and provide API to access a part of
> source waveform. And also we created a record named 
> CompactSubArrayRecord, which uses API above and copy data just it needs.
>
> Unfortunately this mechanism works only for DB-link but not for CA-link.
> (We will need to extend CA protocol to access a part of waveform 
> data,say channel name like "myWaveFormRecord[10:20]")
>
> And also you need to change source code of base.
> We have been using this version of modified base in KEKB and J-PARC and
> encounters no problem caused by this change.
I found your earlier posts on tech-talk also. Thank you very much.

I just looked at the memory consumption of the softIoc running my 
subArrays and finally decided that using a few MB of a reasonable sized 
Linux-Machine is not enough reason to get deeper into this and even 
patch base for this single purpose. I can live with the higher memory 
footprint.
I just stumbled over an unnecessarily high (at first glance) memory usage.

But if one runs into this problem on an IOC with just a few MB of 
memory, your solution seems just perfect to solve this issue.

Thanks again,
Thomas

--
Thomas Birke
Operation Controls

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